I run my internal fans 24/7, I just start with one and add more as the plants mature. It's important to keep up airflow at night to reduce water vapor as the plants are breathing and I personally believe that good airflow is one of the key requirements for top quality bud.
I have gone through more "oscillating" fans than I can count, but they only oscillate for so long. Most of those I've used were made by Secret Jardin (the "20W monkey fan") but they kept replacing them for free as they were in warranty, and when they worked they were great and 100% fit for purpose. By contrast, the 30W non-oscillating fan I have - also by Secret Jardin - has gone non-stop for years, so it's definitely an engineering strain on the fan to oscillate constantly. However, I feel that as long as you have more than one fan going, the oscillation doesn't matter that much, as long as the fans are blowing over the top of the canopy and not directly at a plant.
I recently brought a Garden HighPro 2.0 Clip Fan which so far has gone non-stop for 3 months and no issues... touch wood! You still can't beat a decent floor fan though when it comes to moving air around the tent. I used a RAM 300mm Eco Fan for years and just bought a Bloomroom Airmover which looks identical. These oscillate in a different way which is less of a strain on the motor and they give the whole tent good airflow, including the lower parts of the plant to strengthen stems, decrease larf and reduce the risk of budrot and other nasties.
I hope that helps!